.TH taia 3
.SH NAME
taia \- Temps Atomique International (Attosecond) time routines
.SH SYNTAX
.B #include \(dqtaia.h\(dq

extern int \fBtaia_add\fP(struct taia *\fIt\fR,const struct taia *\fIa\fR,const struct taia *\fIb\fR);
.br
extern int \fBtaia_addsec\fP(struct taia *\fIt\fR,const struct taia *\fIs\fR,int \fIsecs\fR);
.br
extern int \fBtaia_approx\fP(const struct taia *\fIt\fR);
.br
int \fBtaia_frac\fP(const struct taia *\fIt\fR);
.br
extern int \fBtaia_less\fP(const struct tai *\fIa\fR,const struct tai *\fIb\fR);
.br
extern int \fBtaia_now\fP(struct taia *\fIt\fR);
.br
extern int \fBtaia_pack\fP(char *buf,const struct taia *\fIt\fR);
.br
extern int \fBtaia_sub\fP(struct taia *\fIt\fR,const struct taia *\fIa\fR,const struct taia *\fIb\fR);
.br
extern int \fBtaia_tai\fP(const struct taia *\fIt\fR,struct tai *\fIsec\fR);
.br
extern int \fBtaia_uint\fP(struct taia *\fIt\fR,unsigned int \fIsecs\fR);
.br
extern int \fBtaia_unpack\fP(const char *buf,struct taia *\fIt\fR);
.SH DESCRIPTION
.B taia_add 
adds \fIa\fR to \fIb\fR and writes the result to \fIt\fR.
The inputs and output may overlap.

.B taia_addsec 
adds \fIsecs\fR seconds to \fIs\fR and writes the result to \fIt\fR.
The inputs and output may overlap.

.B taia_approx 
returns a double-precision approximation of \fIt\fR. 
The result of 
.B taia_approx 
is always nonnegative.

.B taia_frac 
returns a double-precision approximation to the fraction part
of \fIt\fR. The result of 
.B taia_frac 
is always nonnegative.

.B taia_less 
returns 1 if \fIa\fR is less than \fIb\fR, 0 otherwise.

.B taia_now 
puts the current time into \fIt\fR. More precisely: 
.B tai_now 
puts into \fIt\fR its best guess as to the TAI64NA label 
for the 1-attosecond interval that contains the current time.

This implementation of taia_now assumes that the 
.I time_t 
returned from the time function represents the number of TAI seconds since 1970-01-01
00:00:10 TAI. This matches the convention used by the Olson tz library
in ``right'' mode.

Beware that many clocks are not set accurately, and even the best
scientific clocks are nowhere near 1-attosecond accuracy; however, an
inaccurate clock may still produce reasonably accurate time differences.

.B taia_pack 
converts a TAI64NA label from internal format in \fIt\fR to external
TAI64NA format in \fIbuf\fR.

.B taia_sub 
subtracts \fIb\fR from \fIa\fR and writes the result to \fIt\fR.
The inputs and output may overlap.

.B taia_tai 
places into \fIsec\fR the integer part of \fIt\fR.  If \fIt\fR
contains a TAI64NA label then \fIsec\fR will contain the corresponding
TAI64 label.

.B taia_uint 
converts \fIsecs\fR into a struct taia (setting the fractional part to zero).

.B taia_unpack 
converts a TAI64NA label from external TAI64NA format in
\fIbuf\fR to internal format in \fIt\fR.
.SH "SEE ALSO"
time(1), 
utime(3), 
ctime(3), 
locale(1)